Recent studies in animal models demonstrate that an endogenous human intestinal mucin fragment, termed MUC17, augments intestinal cell restitution and enhances healing of experimental colitis, potentially opening a new door to effective treatment of ulcerative colitis. However, expression of MUC17 in E. coli, yeast, and insect cells has met great challenges due to low expression, improper folding or insolubility. Ventria scientists have developed a highly efficient protein expression system in rice grain and have used the system to produce several proteins which are now in the marketplace. In the present proposal, we would like to test the feasibility of employing the proprietary Ventria rice expression system to produce MUC17 at high levels. Furthermore, we will purify MUC17 from rice grain and test its biological function via in vitro cell culture studies. We hypothesize that MUC17, derived from rice grain, will promote cell migration and inhibit apoptosis, important functions in epithelial cell restitution of the colon. Successfully expressing functional MUC17 in rice grain at high levels will greatly enhance the research and development effort of this project and provide a path to commercialization of this novel protein for patients suffering from ulcerative colitis.